Improved g-as-checx for ordnance



J. W. PEARSON.

Ordnance Gas Vent.

Patented Oct. 12, 1869.

Wain/eases [Wyn 00607"; MW

cited giant J. W. PEARSON, OF NAIERTOVVN, ASSIGNOR TO ALFRED B. ELY,

, OF NEWTON, MASSACHUSETTS.

Letters Patent No. 95,7 20, dated October 12, 1869.

IMPROVED GAS-CHECK IOR ORDNANCE.

The Schedule referred to in these Letters Patent and making part of the same Be it known that I, J. W. PEARSON, of \Vatertown, in the State of Massachusetts, have invented anew and improved Gas-Check for Ordnance, of which the following, with the drawings, is a full description.

Figure 1 is a plan view with check closed.

Figure 2 is a section with check open.

Figure 3 is a section with check closed.

It is well known that the effect of the gases generated by the explosion of the cartridges in heavy 0rdnance is injurious to the inside of the charge-chamber, and in the direction of the touch-hole produces large channels.

My invention is intended to remedy the evil effects of these gases upon the touch-hole of the gun, by enabling them to close the hole at each discharge.

A is a screw-plug, made to screw into the body of the gun at the touch-hole, at being a slot for the screwdriver.

This plug is made hollow from the bottom upward toward the top by a cylindrical cavity, (1.

Into this cavity is introduced a flat-headed bolt 01' piston, B; b the head of the bolt being of the diameter, or nearly so, of the plug at the bottom of its screwthreads.

In the side of the plug is cut a slanting or slightly spiral slot, 0, through which passes a pin, 0, into the piston b. This allows the bolt or piston to move up and down, and, in moving, to turn partially around.

Down through the plug and head of the piston or bolt, the touch-hole is made to pass a; 'y.

' \Vhen the piston is down, a and y will be in line, as infig. 2, but when it is up,-t-hey will be out of'line, as in fig. 3, and a: will be closed.

When the cartridge is placed, and the priming-wire inserted, the piston will be forced down, and x y will be in line for firing. \Vhen the explosion takes place, it will force up the piston, and the head will turn, and the touch-hole x will be closed.

The piston may extend up through the plug, and may have ahead at the upper end or a projecting shank.

Instead of the slot 0 and pin 0, the hollow of the plug and the shank of thepiston may be provided with screw-threads.

The plug may extend above the surface,and have a head, to be manipulated by a wrench, as well as the piston.

What I claim, is-

A gas-check for ordnance, coi'istructed to operate substantially as described.

In testimony whereof, I have hereunto subscribed my name.

J. W. PEARSON. \Vitnesses:

A. B. ELY, ALFRED ELY. 

